Construction of a multi-dimensional flexible MnS based paper electrode with ultra-stable and high-rate capability towards efficient sodium storage.

Recently, there has been an urgent need for flexible and low cost rechargeable batteries for the emerging flexible and wearable electronic devices. Herein, MnS nanoparticles embedded in carbon nanowires/reduced graphene oxide (MnS@CNWs/rGO) composite paper were synthesized via a simple yet scalable strategy with Mn based coordination nanowires and graphene oxide as precursors. The combination of multi-dimensional subunits offers not only a robust structure but also abundant pathways for fast electron/ion diffusion. When directly used as a free-standing electrode for sodium ion batteries (SIBs), the ultra-flexible paper anode exhibits excellent mechanical and electrochemical performance, benefitting from the synergistic effects between nano-dimensional MnS encapsulated in CNWs and conductive rGO nanosheets. Remarkably, a high reversible gravimetric/volumetric capacity of ∼560 mA h g-1/∼362.3 mA h cm-3 is obtained using the self-supported flexible electrode at a current density of 0.1 A g-1, which is almost 92.4% of the theoretical capacity of MnS. More competitively, the flexible MnS@CNWs/rGO anode exhibits an unprecedented long cycle life with a high reversible capacity of ∼150 mA h g-1 at 1 A g-1 after 10, 000 cycles. This highly favours the promising application of MnS@CNWs/rGO paper in advanced flexible SIBs as an appealing anode.